Deodorized calcium chloride



Patented Jan. 7, 1936 PATENT OFFICE.

nnonomznn CALCIUM cnnoamn Charles It. Downs, )ld Greenwiclnconm,as'signor to Weiss and Downs, Inc., New York, N. Y., a corporation ofNew York No Drawing. Application November 15, 1933,

Serial No. 698,123

Claims.

This invention relates to air conditioning and 23, 1933. In saidapplications disclosure is made of an apparatus and method forextracting moisture from air in warm and humid weather through theaction of a deliquescent material such as calcium chloride. The termdeliquescent as employed throughout this specification and in the claimsrefers to a substance which in the solid form is capable upon exposureto humid air of becoming moist and finally liquid and which in itsliquid form has become moist and finally liquefied after such exposureto humid air. A dehumidifying agent such as calcium chloride may be usedto advantage-either with or without an attendant cooling of the airsince the reduced humidity of the air is more healthful and gives asensation of coolness as compared with untreated humid air at the sametemperature.

In my prior applications referred to above,- disclosure is further madeof the employment of the calcium chloride or other treating agent in theform of massive lumps so that an abundant and substantially uniformsurface of the material 30 may be continuously exposed for contact withthe air and liability of clogging the apparatus or the spaces betweenadjacent pieces of material is avoided. Disclosure is further made ofapparatus adapted to collect the solution which drips 35 or flows fromthe lumps of material and to use such solution as a treating agent forthe air in advance of the contact of the air with the solid lumps ofmaterial. The air is thus exposed in the first instance to a dilutesolution, then to successively more concentrated solutions, and finallyto the solid material. I

' Calcium chloride is employed from which a portion of the water ofcrystallization has been removed. When such material takes up the Waterfrom the air heat is given off and provision is therefore made betweenthe stages of exposure to the solid of means for cooling the airsufficiently to restore it to its original temperature. This avoids thedelivery of heated air and keeps down the aqueous tension of thesaturated solution on the surface of the solid. These desirable featuresit is preferred to employ in carrying out the present invention.

When solutions of calcium chloride are evaporated to form lumps suitablefor use in my prior applications'referred to above, air which has beencaused to flow in'- contact therewith has perceptibly the odor of wetplaster which would make this method of air conditioning objectionable.5

It is a feature of the presentinvention that a deodorizing treatment iscombined with the dehumidifying treatment so that the air isdehumidified without being caused to take on an objectionable odor. Thedeodorizing treatment is 10 further efiective to remove or reduce anyobjectionable odors which may have been present in the air beforetreatment and the deodorizing is carried out in an economical andconvenient manner so as to introduce 'no objections to'the 15 use of thedeodorant. Y

Activated carbon is well adapted for utilization as the deodorizingagent because of its large absorptive capacity. It simply placed in thestream of air issuing from the dehumidifying agent, how- 0 ever, thecarbon would have to be in granules of appreciable size to prevent beingtaken up by the air stream and blown into and distributed about thebuilding 'or room into which the air is delivered. Activated carbon ingranular size is the 25 most expensive form of this material. It isdesirable, therefore, to contrive some way of exposing the deodorizingagent in powdered or line sizes to contact with the air while physicallyimprisoning it and preventing its being distributed 30 through the air.

. Filters and other apparatus adapted to subject the air to the elfectof activated carbon after it has left the calcium'chloride would ofnecessity involve the addition of compartments to the mechanism forenabling the air to be thoroughly exposed to the activated carbon. Thiswould increase the resistance to air flow, necessitating the provisionof a more'powerful blower and the consumption of more power.

/ In accordance with a preferred embodimentof the present invention, Iprovide the calcium chloride in lump form .as before but thoroughlyincorporate in the lumps a small quantity of activated carbon, thecarbon being substantially homogeneously mixed with the calciumchloride. With such a composition fresh portions of the activated carbonare progressively exposed as the calcium chloride is consumed. Since thecarbon is exposed only as the calcium chloride takes up enough moisturefrom the air to become dissolved, it is apparent that the carbon willalways be exposed in a moist state and will be kept sufliciently moistto prevent its being taken 5 up by the air stream. The carbon moreover,is exposed at a rate proportional to the rate of consumption of thecalcium chloride and hence there is always an adequate quantity of thecarbon freshly exposed for assuring the delivery of odorless air fromthe dehumidifying apparatus.

As the lumps of calcium chloride are liquefied and the concentratedsolution drains therefrom, (in apparatus such as illustrated in myapplication Ser. No. 672,415) the activated carbon liberated on thesurface of the lumps is conveyed by said solution-into the airpro-drying stage where it .continues to exercise its deodorizingfunction.

The lumps of calcium chloride are formed by evaporating a solution ofcalcium chloride to drive off the water. In accordance with the presentinvention the activated carbon is added to the boiling solution andmixed with it so that when the evaporation is completed and the mass isallowed to cool and solidify the mixture of the carbon throughout themass of calcium chloride is substantially uniform. I have found,however, that it is not expedient to attempt to add the activated carbonto the boiling mass in a dry state since the powdered carbon in thatcase floats on the surface and is blown away to a considerable extent bythe escaping steam bubbles.

In accordance with a preferred method of practicing the presentinvention, therefore, a small quantity of fine activated carbon is firstwetted by thoroughly mixing with water and then added to the boilingsolution of calcium chloride. The carbon is desirably mixed into thesolution in the proportion of substantially two to three pounds ofactivated carbon to one ton of calcium chloride.

This small amount of activated carbon I have found to be sumcient tocomplete y prevent objectionable odors from being introduced by thetreated air into the conditioned space, how much less carbon might beused I am unable to state, a maximum of 2 to 3 lbs of activated carbonper ton of calcium chloride, however, is ample for the purpose ofdeodorization in the normal dwelling-house air.

Calcium chloride crystals may contain six molecules of water ofcrystallization. The evaporation of the mixture is carried beyond thispoint, however, and the heating not discontinued until the water contenthas been reduced to approximately two molecules. After the heating ofthe mass is discontinued, the mixture assumes a plastic condition suchthat it can be easily scored or cut or molded. While in this plasticstate the mass is scored or cut and this scoring persists when the masshas been completely solidified and thus facilitates the breaking of thematerial into lumps of predetermined 'size and shape.

The activated carbon when distributed in preformed lumps of calciumchloride suitable for use in air conditioning apparatus of the typedescribed in my previous applications, is easy .and convenient to handleand may be supplied to the householder or other user of the airconditioning equipment for charging into the apparatus in bags or thelike, in much the same manner as coal is supplied for the furnace inwinter..

The lumps may be preformed to the desired size and as theactivated-carbon is distributed therethrough in the right amount fordeodorization, the combination is much more efficient and satisfactorythan the use of activated carbon in a separate compartment of theapparatus for deodorization.

In the foregoing description calcium chloride has been referred toillustratively as the dehumidifying agent employed, and activated carbonhas been referred to illustratively as the deodorizing agent employed.These ingredients are the preferred ingredients both because of theirgreat efiiciency in performing the functions required of them andbecause they are chemically inert to one another. It will beappreciated, however, that other deliquescent substances and otherdeodorants might be employed without departing from the spirit and scopeof the present invention.

While I have described what I believe to be the best embodiment of myinvention, it will be understood that instead of intimately mixing theactivated carbon with the calcium chloridein the liquid state prior tolump formation that other methods of mixing the carbon with the calciumchloride could be used. It is possible, for example, to add theactivated carbon to a solution of calcium chloride which is used fordehumidification as described in mycopending applications above referredto. I do not wish, therefore, to be confined to the embodimentsdescribed, but what I desire to cover by Letters Patent is set forth inthe appended claims.

I claim:

1. A composition of matter for use in air conditioning, consisting ofdeliquescent lumps of solid non-porous calcium chloride with activatedcarbon uniformly distributed through each lump.

2. A dehumidifying agent for use in air conditicning apparatus composedof lumps of material, the lumps consisting of a deliquescent solid andfinely divided activated carbon homogeneously mixed within the lumps andheld thereby.

3. A dehumidifying agent composed of lumps of material, the lumpsconsisting of solid calcium chloride and a finely divided soliddeodorizing agent homogeneously mixed within the lamps and held thereby.

4. A dehumidifying agent composed of lumps of material, the lumpscomprising solid calcium chloride and finely divided activated carbonhomogeneously mixed within the lumps and held thereby, the ingredientsbeing mixed in the ratio of two or three pounds of carbon to one ton ofcalcium chloride.

5. The method of dehumidifying air, which comprises causing the air toflow incontact'with a deliquescent material and with a solid deodorant,and progressively exposing fresh portions of the deodorant for contactwith the air at a rate -proportional to the rate of consumption of thedeliquescent material. I

6. The method of dehumidifying air which comprises providing lumps ofhomogeneously combined deliquescent material and solid deodorant andcausing air to flow in contact with said lumps and progressivelyexposing fresh portions of the deodorant for contact with the air at arate proportional to the rate of consumption of the deliquescentmaterial.

7. The method of dehumidifying air, which comprises causing the air toflow in contact with a deliquescent material in lump form having a soliddeodorant uniformly distributed therethrough, and progressively exposingfresh portions of the deodorant for contact with the air at a rateproportional to the rate of liquefaction of the deliquescent material.

8. The method of dehumidifying air which comprises causing the air toflow in contact with o lump and held thereby.

of finely divided activated carbon mixed therein, and subsequentlycausing the air to flow in contact with lumps of homogeneously combinedcalcium chloride and activated carbon.

9. As an article of manufacture for use in-air conditioning apparatus,preformed lumps consisting of solid calcium chloride and finely dividedactivated carbon distributed within the 3 10. The method a damn; airwhich comprises causing the air to flow in contact with solid calciumchloride and with activated carbon and progressively exposing freshportions of the activated carbon for contact with the air at a rateproportional to the rate of consumption of the solid calcium chloride.

'cmnms R. DOWNS.

